/*
 * Copyright 2017 Google
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import "FSparseSnapshotTests.h"
#import "FSparseSnapshotTree.h"
#import "FSnapshotUtilities.h"
#import "FEmptyNode.h"

@implementation FSparseSnapshotTests

- (void) testBasicRememberAndFind {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    FPath* path = [[FPath alloc] initWith:@"a/b"];
    id<FNode> node = [FSnapshotUtilities nodeFrom:@"sdfsd"];

    [st rememberData:node onPath:path];
    id<FNode> found = [st findPath:path];
    XCTAssertFalse([found isEmpty], @"Should find node");
    found = [st findPath:path.parent];
    XCTAssertTrue(found == nil, @"Should not find a node");
}

- (void) testFindInsideAnExistingSnapshot {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    FPath* path = [[FPath alloc] initWith:@"t/tt"];
    id<FNode> node = [FSnapshotUtilities nodeFrom:@{@"a": @"sdfsd", @"x": @5, @"999i": @YES}];
    id<FNode> update = [FSnapshotUtilities nodeFrom:@{@"goats": @88}];
    node = [node updateImmediateChild:@"apples" withNewChild:update];
    [st rememberData:node onPath:path];

    id<FNode> found = [st findPath:path];
    XCTAssertFalse([found isEmpty], @"Should find the node we set");
    found = [st findPath:[path childFromString:@"a"]];
    XCTAssertTrue([[found val] isEqualToString:@"sdfsd"], @"Find works inside data snapshot");
    found = [st findPath:[path childFromString:@"999i"]];
    XCTAssertTrue([[found val] isEqualToNumber:@YES], @"Find works inside data snapshot");
    found = [st findPath:[path childFromString:@"apples"]];
    XCTAssertFalse([found isEmpty], @"Should find the node we set");
    found = [st findPath:[path childFromString:@"apples/goats"]];
    XCTAssertTrue([[found val] isEqualToNumber:@88], @"Find works inside data snapshot");
}

- (void) testWriteASnapshotInsideASnapshot {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:@{@"a": @{@"b": @"v"}}] onPath:[[FPath alloc] initWith:@"t"]];
    [st rememberData:[FSnapshotUtilities nodeFrom:@19] onPath:[[FPath alloc] initWith:@"t/a/rr"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"t/a/b"]];
    XCTAssertTrue([[found val] isEqualToString:@"v"], @"Find inside snap");
    found = [st findPath:[[FPath alloc] initWith:@"t/a/rr"]];
    XCTAssertTrue([[found val] isEqualToNumber:@19], @"Find inside snap");
}

- (void) testWriteANullValueAndConfirmItIsRemembered {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:[NSNull null]] onPath:[[FPath alloc] initWith:@"awq/fff"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"awq/fff"]];
    XCTAssertTrue([found isEmpty], @"Empty node");
    found = [st findPath:[[FPath alloc] initWith:@"awq/sdf"]];
    XCTAssertTrue(found == nil, @"No node here");
    found = [st findPath:[[FPath alloc] initWith:@"awq/fff/jjj"]];
    XCTAssertTrue([found isEmpty], @"Empty node");
    found = [st findPath:[[FPath alloc] initWith:@"awq/sdf/sdj/q"]];
    XCTAssertTrue(found == nil, @"No node here");
}

- (void) testOverwriteWithNullAndConfirmItIsRemembered {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:@{@"a": @{@"b": @"v"}}] onPath:[[FPath alloc] initWith:@"t"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertFalse([found isEmpty], @"non-empty node");
    [st rememberData:[FSnapshotUtilities nodeFrom:[NSNull null]] onPath:[[FPath alloc] initWith:@"t"]];
    found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertTrue([found isEmpty], @"Empty node");
}

- (void) testSimpleRememberAndForget {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:@{@"a": @{@"b": @"v"}}] onPath:[[FPath alloc] initWith:@"t"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertFalse([found isEmpty], @"non-empty node");
    [st forgetPath:[[FPath alloc] initWith:@"t"]];
    found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertTrue(found == nil, @"node is gone");
}

- (void) testForgetTheRoot {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:@{@"a": @{@"b": @"v"}}] onPath:[[FPath alloc] initWith:@"t"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertFalse([found isEmpty], @"non-empty node");
    found = [st findPath:[[FPath alloc] initWith:@""]];
    XCTAssertTrue(found == nil, @"node is gone");
}

- (void) testForgetSnapshotInsideSnapshot {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:[FSnapshotUtilities nodeFrom:@{@"a": @{@"b": @"v", @"c": @9, @"art": @NO}}] onPath:[[FPath alloc] initWith:@"t"]];
    id<FNode> found = [st findPath:[[FPath alloc] initWith:@"t/a/c"]];
    XCTAssertFalse([found isEmpty], @"non-empty node");
    found = [st findPath:[[FPath alloc] initWith:@"t"]];
    XCTAssertFalse([found isEmpty], @"non-empty node");
    [st forgetPath:PATH(@"t/a/c")];
    XCTAssertTrue([st findPath:PATH(@"t")] == nil, @"no more node here");
    XCTAssertTrue([st findPath:PATH(@"t/a")] == nil, @"no more node here");
    XCTAssertTrue([[[st findPath:PATH(@"t/a/b")] val] isEqualToString:@"v"], @"child still exists");
    XCTAssertTrue([st findPath:PATH(@"t/a/c")] == nil, @"no more node here");
    XCTAssertTrue([[[st findPath:PATH(@"t/a/art")] val] isEqualToNumber:@NO], @"child still exists");
}

- (void) testPathShallowerThanSnapshots {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:NODE(@NO) onPath:PATH(@"t/x1")];
    [st rememberData:NODE(@YES) onPath:PATH(@"t/x2")];

    [st forgetPath:PATH(@"t")];
    XCTAssertTrue([st findPath:PATH(@"t")] == nil, @"No more node here");
}

- (void) testIterateChildren {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    id<FNode> node = [FSnapshotUtilities nodeFrom:@{@"b": @"v", @"c": @9, @"art": @NO}];
    [st rememberData:node onPath:PATH(@"t")];
    [st rememberData:[FEmptyNode emptyNode] onPath:PATH(@"q")];

    __block int num = 0;
    __block BOOL gotT = NO;
    __block BOOL gotQ = NO;
    [st forEachChild:^(NSString* key, FSparseSnapshotTree* tree) {
        num++;
        if ([key isEqualToString:@"t"]) {
            gotT = YES;
        } else if ([key isEqualToString:@"q"]) {
            gotQ = YES;
        } else {
            XCTFail(@"Unknown child");
        }
    }];

    XCTAssertTrue(gotT, @"Saw t");
    XCTAssertTrue(gotQ, @"Saw q");
    XCTAssertTrue(num == 2, @"Saw two children");
}

- (void) testIterateTrees {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    __block int count = 0;
    [st forEachTreeAtPath:PATH(@"") do:^(FPath *path, id<FNode> data) {
        count++;
    }];
    XCTAssertTrue(count == 0, @"No trees to iterate through");

    [st rememberData:NODE(@1) onPath:PATH(@"t")];
    [st rememberData:NODE(@2) onPath:PATH(@"a/b")];
    [st rememberData:NODE(@3) onPath:PATH(@"a/x/g")];
    [st rememberData:NODE([NSNull null]) onPath:PATH(@"a/x/null")];

    __block int num = 0;
    __block BOOL got1 = NO;
    __block BOOL got2 = NO;
    __block BOOL got3 = NO;
    __block BOOL gotNull = NO;

    [st forEachTreeAtPath:PATH(@"q") do:^(FPath *path, id<FNode> data) {
        num++;
        NSString* pathString = [path description];
        if ([pathString isEqualToString:@"/q/t"]) {
            got1 = YES;
            XCTAssertTrue([[data val] isEqualToNumber:@1], @"got 1");
        } else if ([pathString isEqualToString:@"/q/a/b"]) {
            got2 = YES;
            XCTAssertTrue([[data val] isEqualToNumber:@2], @"got 2");
        } else if ([pathString isEqualToString:@"/q/a/x/g"]) {
            got3 = YES;
            XCTAssertTrue([[data val] isEqualToNumber:@3], @"got 3");
        } else if ([pathString isEqualToString:@"/q/a/x/null"]) {
            gotNull = YES;
            XCTAssertTrue([data val] == [NSNull null], @"got null");
        } else {
            XCTFail(@"unknown tree");
        }
    }];

    XCTAssertTrue(got1 && got2 && got3 && gotNull, @"saw all the children");
    XCTAssertTrue(num == 4, @"Saw the right number of children");
}

- (void) testSetLeafAndForgetDeeperPath {
    FSparseSnapshotTree* st = [[FSparseSnapshotTree alloc] init];
    [st rememberData:NODE(@"bar") onPath:PATH(@"foo")];
    BOOL safeToRemove = [st forgetPath:PATH(@"foo/baz")];
    XCTAssertFalse(safeToRemove, @"Should not have deleted anything, nothing to remove");
}

@end
